Ten years after former president Bill
Clinton announced that the first draft of the human genome was complete,
medicine has yet to see any large part of the promised benefits.
For
biologists, the genome has yielded one insightful surprise after another. But
the primary goal of the $3 billion Human Genome Project — to ferret out
the genetic roots of common diseases like cancer and Alzheimer's and then
generate treatments — remains largely elusive. Indeed, after 10 years of
effort, geneticists are almost back to square one in knowing where to look for
the roots of common disease.
One sign of the genome's limited use
for medicine so far was a recent test of genetic predictions for heart disease.
A medical team led by Nina Paynter of Brigham and Women's Hospital in Boston
collected 101 genetic variants that had been statistically linked to heart
disease in various genome-scanning studies. But the variants turned out to have
no value in forecasting disease among 19,000 women who had been followed for 12
years.
The old-fashioned method of taking a family history was a
better guide, Paynter reported this February in the Journal of the American
Medical Association.
In announcing on June 26, 2000, that the first
draft of the human genome had been achieved, Clinton said it would
"revolutionize the diagnosis, prevention and treatment of most, if not all,
human diseases."
At a news conference, Francis Collins, then the
director of the genome agency at the National Institutes of Health, said that
genetic diagnosis of diseases would be accomplished in 10 years and that
treatments would start to roll out perhaps five years after that. "Over the
longer term, perhaps in another 15 or 20 years," he added, "you will see a
complete transformation in therapeutic medicine."
The pharmaceutical
industry has spent billions of dollars to reap genomic secrets and is starting
to bring several genome-guided drugs to market. While drug companies continue to
pour huge amounts of money into genome research, it has become clear that the
genetics of most diseases are more complex than anticipated and that it will
take many more years before new treatments may be able to transform medicine.
"Genomics is a way to do science, not medicine," said Harold Varmus,
president of the Memorial Sloan-Kettering Cancer Center in New York, who in July
will become the director of the National Cancer Institute. The last decade has
brought a flood of discoveries of disease-causing mutations in the human genome.
But with most diseases, the findings have explained only a small part of the
risk of getting the disease. And many of the genetic variants linked to
diseases, some scientists have begun to fear, could be statistical illusions.
The Human Genome Project was started in 1989 with the goal of
sequencing, or identifying, all three billion chemical units in the human
genetic instruction set, finding the genetic roots of disease and then
developing treatments. With the sequence in hand, the next step was to identify
the genetic variants that increase the risk for common diseases like cancer and
diabetes.
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